<Swing Dev> [13] RFR JDK-8214702:Wrong text position for whitespaced string in printing Swing text

[Sergey Bylokhov]

On 13/02/2019 22:53, Prasanta Sadhukhan wrote:
> Hi Sergey,
> 
> I believe drawChars() also has same printing issue [and should be changed like modified drawString()] but I am not able to test it as reproducer testcase uses JLabel whose constructor can only accept "String" and not char[] so I can only test drawString(). Using drawChars() implementation in drawString() still reproduces the issue.

Is it possible temporary replace the call to drawString() by the drawChars(), to check how drawChars() will work?
or probably we can implement drawChars() on top of drawString()?

> 
> Regards
> Prasanta
> On 14-Feb-19 4:12 AM, Sergey Bylokhov wrote:
>> Hi, Prasanta.
>>
>>> I modified the fix to use deviceFRC if not compatible and in sync with the comment which says "obtain a TextLayout with advances for the printer graphics FRC"
>>> I used SwingUtilies2.getStringWidth() which calculates the advances of the string if text layouting is used.
>>>
>>> http://cr.openjdk.java.net/~psadhukhan/8214702/webrev.2/
>>
>> Can you please take a look to the existed drawChars() method, which is implemented in the similar way as drawStringImpl() and new version of drawString(), but they have some small difference. Why we cannot use the same logic?
>>
>> For example in the drawChars:
>> =========
>>             FontRenderContext deviceFontRenderContext = g2d.
>>                 getFontRenderContext();
>>             FontRenderContext frc = getFontRenderContext(c);
>>             if (frc != null &&
>>                 !isFontRenderContextPrintCompatible
>>                 (deviceFontRenderContext, frc)) {
>>                  String text = new String(data, offset, length);
>>                  TextLayout layout = new TextLayout(text, g2d.getFont(),
>>                                deviceFontRenderContext);
>>                  String trimmedText = trimTrailingSpaces(text);
>>                  if (!trimmedText.isEmpty()) {
>>                      float screenWidth = (float)g2d.getFont().
>>                          getStringBounds(trimmedText, frc).getWidth();
>>                      layout = layout.getJustifiedLayout(screenWidth);
>>
>> ==========
>> Similar but not the same logic in the fix:
>>
>>  524                 FontRenderContext frc = getFontRenderContext(c);
>>  525                 if (frc.isAntiAliased() || frc.usesFractionalMetrics()) {
>>  526                     frc = new FontRenderContext(frc.getTransform(), false, false);
>>  527                 }
>>  528                 FontRenderContext deviceFRC = g2d.getFontRenderContext();
>>  529                 String trimmedText = trimTrailingSpaces(text);
>>  530                 if (!trimmedText.isEmpty()) {
>>  531                     FontMetrics fm = g2d.getFontMetrics();
>>  532                     float screenWidth = SwingUtilities2.stringWidth(c, fm ,trimmedText);
>>  533                     TextLayout layout;
>>  534                     if (!isFontRenderContextPrintCompatible(frc, deviceFRC)) {
>>  535                         layout = createTextLayout(c, text, g2d.getFont(), deviceFRC);
>>  536                     } else {
>>  537                         layout = createTextLayout(c, text, g2d.getFont(), frc);
>>  538                     }
>>  540                     layout = layout.getJustifiedLayout(screenWidth);
>>
>>
>>
> 


-- 
Best regards, Sergey.